Apparatus and method for controlling fluid flow

Abstract

An actuator base, bobbin, and pole piece form a pocket for an armature that a flexible membrane encloses to form an armature chamber filled with an incompressible fluid. The membrane protects the armature from exposure to corrosive fluids flowing in a conduit. Conduit flow can be stopped by driving the membrane against a valve seat. Pressure from the controlled fluid in the conduit is transmitted through the membrane to the fluid within the armature chamber so that the armature does not need to counteract force applied to the membrane by the conduit fluid's pressure.

1. An electromagnetic actuator, comprising:
 a solenoid coil and an armature housing constructed and arranged to receive a ferromagnetic armature including a distal part,  
 a membrane secured with respect to said armature housing and arranged to enclose at least partially said distal part to seal armature fluid within an armature pocket providing a volume for said armature fluid, wherein displacement of said distal part displaces said membrane with respect to a valve passage controlled by said actuator,  
 an actuator base arranged with a pilot body member and said membrane to provide a valve comprising said valve passage, said valve including a valve seat arranged for contact with said membrane, and  
 an armature port providing a fluid passage to enable flow of said armature fluid between said distal part and a proximal part of said armature thereby enabling rapid linear movement of said armature with respect to said armature housing during opening and closing of said valve passage, wherein said armature fluid is enclosed within said volume during said movement.  
 
   
   
     2. The actuator of  claim 1  wherein said pilot body member is attached to said actuator base to provide a known, substantially constant distance between an external surface of said membrane and said valve seat. 
   
   
     3. The actuator of  claim 1  wherein said body member includes a shoulder cooperatively designed with respect to said actuator base to provide a reproducible stop and thereby achieve a known, substantially constant distance when attaching said pilot body member to said actuator base. 
   
   
     4. The actuator of  claim 1  wherein said membrane includes a compliant region, and a resilient region designed to be displaced by said distal part of said armature and designed to come in contact with said valve seat. 
   
   
     5. The actuator of  claim 4  wherein said resilient region is further designed to be attached to said distal part of said armature. 
   
   
     6. The actuator of  claim 5  wherein said resilient region includes a C-shaped member designed for said attachment to said distal part. 
   
   
     7. The actuator of  claim 1  constructed for controlling water flow. 
   
   
     8. The actuator of  claim 7  constructed for controlling water flow in a water flushing system. 
   
   
     9. The actuator of  claim 7  constructed for controlling water flow in an irrigation system. 
   
   
     10. The actuator of  claim 1 , wherein said solenoid coil is coupled to a control circuit constructed and arranged to apply a coil drive for actuating said linear movement of said armature. 
   
   
     11. The actuator system of  claim 10  further including a presence sensor constructed and arranged to provide electrical signals to said control circuit. 
   
   
     12. The actuator system of  claim 10  further including a motion sensor constructed and arranged to provide electrical signals to said control circuit. 
   
   
     13. An electromagnetic actuator, comprising:
 a solenoid coil and an armature housing constructed and arranged to receive a ferromagnetic armature including a distal part,  
 a membrane secured with respect to said armature housing and arranged to enclose at least partially said distal part to seal armature fluid within an armature pocket providing a volume for said armature fluid, wherein displacement of said distal part displaces said membrane with respect to a valve passage controlled by said actuator, and  
 an armature port providing a fluid passage to enable flow of said armature fluid between said distal part and a proximal part of said armature thereby enabling rapid linear movement of said armature with respect to said armature housing during opening and closing of said valve passage, wherein said armature fluid is enclosed within said volume during said movement,  
 wherein said distal part of the armature is arranged to compress said membrane against a valve seat when said armature is disposed in its extended armature position, and  
 wherein a ratio that the area of said distal part bears to the area of said membrane exposed to a conduit upstream of the membrane is between 1.4 and 12.3.  
 
   
   
     14. The actuator of  claim 13 , wherein said solenoid coil is coupled to a control circuit constructed and arranged to apply a coil drive for actuating said linear movement of said armature. 
   
   
     15. The actuator system of  claim 14  further including a motion sensor. 
   
   
     16. The actuator system of  claim 14  further including a presence sensor. 
   
   
     17. The actuator of  claim 13  wherein said membrane includes a compliant region, and a resilient region designed to be displaced by said distal part of said armature and designed to come in contact with said valve seat. 
   
   
     18. The actuator of  claim 17  wherein said resilient region is further designed to be attached to said distal part of said armature. 
   
   
     19. The actuator of  claim 18  wherein said resilient region includes a C-shaped member designed for said attachment to said distal part. 
   
   
     20. The actuator of  claim 13  constructed for controlling water flow. 
   
   
     21. The actuator of  claim 20  constructed for controlling water flow in a water flushing system. 
   
   
     22. The actuator of  claim 20  constructed for controlling water flow in an irrigation system. 
   
   
     23. The actuator of  claim 13  further including a permanent magnet arranged to form a latching actuator. 
   
   
     24. The actuator of  claim 23  further including a bias spring positioned and arranged to bias said armature toward its extended position. 
   
   
     25. The actuator of  claim 24  wherein said fluid passage is located within said ferromagnetic armature and is constructed to receive said bias spring. 
   
   
     26. The actuator of  claim 13  wherein said armature fluid includes incompressible fluid comprising a corrosion inhibitor. 
   
   
     27. The actuator of  claim 13  wherein said armature fluid includes an incompressible fluid having a large molecule. 
   
   
     28. A method of operating an actuator, comprising the steps of
 providing a solenoid coil and an armature housing constructed and arranged to receive an armature including a distal part,  
 providing a membrane secured with respect to said armature housing and arranged to enclose at least partially said distal part to seal armature fluid within an armature pocket providing a volume, wherein displacement of said distal part displaces said membrane with respect to a valve passage controlled by said actuator,  
 providing an armature port enabling a fluid passage to enable flow of said armature fluid between said distal part and a proximal part of said armature, and  
 delivering a drive signal to said solenoid coil to provide opening and closing of said valve passage by linearly displacing said armature, wherein said armature fluid is enclosed within said volume during said opening and closing,  
 wherein said opening and closing includes traversing a known, substantially constant distance between an external surface of said membrane and a valve seat of said valve passage.  
 
   
   
     29. The method of  claim 28 , wherein said opening and closing includes displacing a resilient region of said membrane designed to be attached to said distal part of said armature. 
   
   
     30. The method of  claim 28 , wherein said opening and closing includes displacing a resilient region of said membrane designed to be attached to said distal part of said armature, wherein said resilient region includes a C-shaped member designed for said attachment to said distal part. 
   
   
     31. A method of operating an actuator, comprising the steps of
 providing a solenoid coil and an armature housing constructed and arranged to receive an armature including a distal part,  
 providing a membrane secured with respect to said armature housing and arranged to enclose at least partially said distal part to seal armature fluid within an armature pocket providing a volume, wherein displacement of said distal part displaces said membrane with respect to a valve passage controlled by said actuator,  
 providing an armature port enabling a fluid passage to enable flow of said armature fluid between said distal part and a proximal part of said armature,  
 receiving a signal from a motion sensor, and  
 delivering a drive signal to said solenoid coil to provide opening and closing of said valve passage by linearly displacing said armature, wherein said armature fluid is enclosed within said volume during said opening and closing.  
 
   
   
     32. A method of operating an actuator, comprising the steps of
 providing a solenoid coil and an armature housing constructed and arranged to receive an armature including a distal part,  
 providing a membrane secured with respect to said armature housing and arranged to enclose at least partially said distal part to seal armature fluid within an armature pocket providing a volume, wherein displacement of said distal part displaces said membrane with respect to a valve passage controlled by said actuator,  
 providing an armature port enabling a fluid passage to enable flow of said armature fluid between said distal part and a proximal part of said armature,  
 receiving a signal from a presence sensor, and  
 delivering a drive signal to said solenoid coil to provide opening and closing of said valve passage by linearly displacing said armature, wherein said armature fluid is enclosed within said volume during said opening and closing.